This article is about the audio object. For the online music publication see
soundgenerator.com. A sound generator is a vibrating object which produces a sound. There are two main kinds of sound generators (thus, two main kinds of
musical instruments). A full cycle of a sound wave will be described in each example which consists of initial normal conditions (no fluctuations in atmospheric pressure), an increase of air pressure, a subsequent decrease in air pressure which brings it back to normal, a decrease in air pressure (less pressure than initial conditions), and lastly, an increase which brings atmospheric pressure back to normal again. Therefore, the final conditions are the same as the initial, at-rest conditions.
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